diff --git a/packages/devextreme/js/viz/chart.d.ts b/packages/devextreme/js/viz/chart.d.ts
index b6a13f884b56..7bcde2a8f144 100644
--- a/packages/devextreme/js/viz/chart.d.ts
+++ b/packages/devextreme/js/viz/chart.d.ts
@@ -1645,7 +1645,7 @@ export type ArgumentAxisLabel = CommonAxisSettingsLabel & {
      * @default undefined
      * @public
      */
-    format?: Format;
+    format?: Format | undefined;
 };
 /**
  * @public